1. Field of the Invention
This invention relates to an image forming apparatus using an electrophotographic system, e.g., a photocopier, a printer, a facsimile machine, or the like, and an assembling method for the image forming apparatus.
2. Description of Related Art
As image forming apparatuses capable of printing multicolor typing such as color photocopiers and color printers, a multiple image forming apparatus as set forth in Japanese Unexamined Patent Publication No. 63-271,275 can be exemplified. Furthermore, in recent years, high speed operation is demanded, and from this context, the embodiments of the image forming apparatus described in the Gazette are frequently used.
In a full color type image forming apparatus having four photosensitive drums, each toner image formed on each photosensitive drum is transferred sequentially onto a transfer medium, so that if a parallel degree between the image forming sections of the respective colors (or a parallel degree in an axial direction of the respective photosensitive drums) is not proper the apparatus suffers color shifts as problems.
To solve these problems, as described in Japanese Unexamined Patent Publication No. 64-84,263, some conventional apparatus had a structure that a face plate individually adjustably mounting adjusting members for supporting other end of the structural members in an axial direction is secured to a body frame located on a front side of the apparatus where one end in the axial direction of the structural members composed of an image carrier, an exposing means, a transfer means, etc. is supported to a securing position of the body frame on a rear side.
However, such a conventional apparatus is adjusted in mounting, to the body frame, the image carrier, the exposing means, the transfer means, etc. respectively serving as the structural members for the image forming means, and therefore, it is difficult to adjust the parallel degree between the structural members such as the image carrier and the like constituting the image forming means, and adjusting the parallel degree takes so much time.
It is an object of the invention to provide an image forming apparatus capable of easily adjusting mutual parallel degrees among plural image carriers, and mutual parallel degrees among plural exposing means and plural image carriers and capable of preventing color shifts from occurring in the images formed on a transfer medium.
Other objects of the invention become apparent when the following detailed description is read.